package cn.csl.basics.util;

import java.text.ParseException;  
import java.text.SimpleDateFormat;  
import java.util.Date;

public class RelativeDateFormat {  
	  
	    private static final long ONE_MINUTE = 60000L;  
	    private static final long ONE_HOUR = 3600000L;  
	    private static final long ONE_DAY = 86400000L;  
	    private static final long ONE_WEEK = 604800000L;  
	  
	    private static final String ONE_SECOND_AGO = "秒前";  
	    private static final String ONE_MINUTE_AGO = "分钟前";  
	    private static final String ONE_HOUR_AGO = "小时前";  
	    private static final String ONE_DAY_AGO = "天前";  
	    private static final String ONE_MONTH_AGO = "月前";  
	    private static final String ONE_YEAR_AGO = "年前";  
	  
	    public static void main(String[] args) throws ParseException {  
	        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:m:s");  
	        Date date = format.parse("2017-03-27 17:00:35");  
	        System.out.println(format(date));  
	    }  
	  
	    public static String format(Date date) {  
	        long delta = new Date().getTime() - date.getTime();  
	        if (delta < 1L * ONE_MINUTE) {  
	            long seconds = toSeconds(delta);  
	            return (seconds <= 0 ? 1 : seconds) + ONE_SECOND_AGO;  
	        }  
	        if (delta < 45L * ONE_MINUTE) {  
	            long minutes = toMinutes(delta);  
	            return (minutes <= 0 ? 1 : minutes) + ONE_MINUTE_AGO;  
	        }  
	        if (delta < 24L * ONE_HOUR) {  
	            long hours = toHours(delta);  
	            return (hours <= 0 ? 1 : hours) + ONE_HOUR_AGO;  
	        }  
	        if (delta < 48L * ONE_HOUR) {  
	            return "昨天";  
	        }  
	        if (delta < 30L * ONE_DAY) {  
	            long days = toDays(delta);  
	            return (days <= 0 ? 1 : days) + ONE_DAY_AGO;  
	        }  
	        if (delta < 12L * 4L * ONE_WEEK) {  
	            long months = toMonths(delta);  
	            return (months <= 0 ? 1 : months) + ONE_MONTH_AGO;  
	        } else {  
	            long years = toYears(delta);  
	            return (years <= 0 ? 1 : years) + ONE_YEAR_AGO;  
	        }  
	    }  
	  
	    private static long toSeconds(long date) {  
	        return date / 1000L;  
	    }  
	  
	    private static long toMinutes(long date) {  
	        return toSeconds(date) / 60L;  
	    }  
	  
	    private static long toHours(long date) {  
	        return toMinutes(date) / 60L;  
	    }  
	  
	    private static long toDays(long date) {  
	        return toHours(date) / 24L;  
	    }  
	  
	    private static long toMonths(long date) {  
	        return toDays(date) / 30L;  
	    }  
	  
	    private static long toYears(long date) {  
	        return toMonths(date) / 365L;  
	    }  
}
